Detecting and measuring a coring sample

ABSTRACT

Detecting and measuring the presence of a coring sample within a coring tool. These include moving a handling piston of the coring tool from a first position to a second position with respect to the coring tool, measuring a distance of the movement of the handling piston between the first position and the second position, comparing the measured distance with a predetermined distance, and determining if a coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.

BACKGROUND OF THE DISCLOSURE

Wells are generally drilled into the ground or ocean bed to recover natural deposits of oil and gas, as well as other desirable materials that are trapped in geological formations in the Earth's crust. Wells are typically drilled using a drill bit attached to the lower end of a “drill string.” Drilling fluid, or mud, is typically pumped down through the drill string to the drill bit. The drilling fluid lubricates and cools the bit, and may additionally carry drill cuttings from the borehole back to the surface.

In various oil and gas exploration operations, it may be beneficial to have information about the subsurface formations that are penetrated by a borehole. For example, certain formation evaluation schemes include measurement and analysis of the formation pressure and permeability. These measurements may be essential to predicting the production capacity and production lifetime of the subsurface formation.

Further, in addition to the formation testing tools, which may be primarily used to collect fluid samples, samples may also be taken of the formation rock within the borehole. For example, a coring tool may be used to take a coring sample of the formation rock within the borehole. The typical coring tool usually includes a hollow drill bit, such as a coring bit, that is advanced into the formation wall such that a sample, such as a coring sample, may be removed from the formation. Downhole coring operations generally include axial coring and sidewall coring. In axial coring, the coring tool may be disposed at the end of a drill string disposed within a borehole, in which the coring tool may be used to collect a coring sample at the bottom of the borehole. In sidewall coring, the coring bit from the coring tool may extend radially from the coring tool, in which the coring tool may be used to collect a coring sample from a side wall of the borehole.

As such, the coring sample may then be transported to the surface, in which the sample may be analyzed to assess, amongst other things, the reservoir storage capacity (porosity) and the permeability of the material that makes up the formation surrounding the borehole, such as the chemical and mineral composition of the fluids and mineral deposits contained in the pores of the formation and/or the irreducible water content contained in the formation. However, traditional coring tools may be limited in operation, such as by having limited storage area for coring samples, and further may not reliably break core samples away from the formation of the borehole.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

FIG. 1 shows a side view of a wellsite having a drilling rig with a drill string suspended therefrom in accordance with one or more embodiments of the present disclosure.

FIG. 2 shows a side view of a tool in accordance with one or more embodiments of the present disclosure.

FIG. 3 shows a schematic view of a tool in accordance with one or more embodiments of the present disclosure.

FIG. 4 shows a side view of a tool in accordance with one or more embodiments of the present disclosure.

FIG. 5 shows a side view of a tool in accordance with one or more embodiments of the present disclosure.

FIG. 6 shows a side view of a wellsite having a drilling rig in accordance with one or more embodiments of the present disclosure.

FIGS. 7A and 7B show multiple views of a coring tool in accordance with one or more embodiments of the present disclosure.

FIG. 8 shows a schematic view of a coring tool in accordance with one or more embodiments of the present disclosure.

FIGS. 9A-9D show multiple side views of a coring tool in accordance with one or more embodiments of the present disclosure.

FIG. 10 shows a schematic view of a coring tool in accordance with one or more embodiments of the present disclosure.

FIGS. 11 and 12 show multiple views of flow charts of methods and to drill with a coring tool in accordance with one or more embodiments of the present disclosure.

FIG. 13 shows a computer system that may be used in accordance with an embodiment disclosed herein.

DETAILED DESCRIPTION

It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact.

Referring now to FIG. 1, a side view of a wellsite 100 having a drilling rig 110 with a drill string 112 suspended therefrom in accordance with one or more embodiments of the present disclosure is shown. The wellsite 100 shown, or one similar thereto, may be used within onshore and/or offshore locations. In this embodiment, a borehole 114 may be formed within a subsurface formation F, such as by using rotary drilling, or any other method known in the art. As such, one or more embodiments in accordance with the present disclosure may be used within a wellsite, similar to the one as shown in FIG. 1 (discussed more below). Further, those having ordinary skill in the art will appreciate that the present disclosure may be used within other wellsites or drilling operations, such as within a directional drilling application, without departing from the scope of the present disclosure.

Continuing with FIG. 1, the drill string 112 may suspend from the drilling rig 110 into the borehole 114. The drill string 112 may include a bottom hole assembly 118 and a drill bit 116, in which the drill bit 116 may be disposed at an end of the drill string 112. The surface of the wellsite 100 may have the drilling rig 110 positioned over the borehole 114, and the drilling rig 110 may include a rotary table 120, a kelly 122, a traveling block or hook 124, and may additionally include a rotary swivel 126. The rotary swivel 126 may be suspended from the drilling rig 110 through the hook 124, and the kelly 122 may be connected to the rotary swivel 126 such that the kelly 122 may rotate with respect to the rotary swivel.

Further, an upper end of the drill string 112 may be connected to the kelly 122, such as by threadingly connecting the drill string 112 to the kelly 122, and the rotary table 120 may rotate the kelly 122, thereby rotating the drill string 112 connected thereto. As such, the drill string 112 may be able to rotate with respect to the hook 124. Those having ordinary skill in the art, however, will appreciate that though a rotary drilling system is shown in FIG. 1, other drilling systems may be used without departing from the scope of the present disclosure. For example, a top-drive (also known as a “power swivel”) system may be used in accordance with one or more embodiments without departing from the scope of the present disclosure. In such a top-drive system, the hook 124, swivel 126, and kelly 122 are replaced by a drive motor (electric or hydraulic) that may apply rotary torque and axial load directly to drill string 112.

The wellsite 100 may further include drilling fluid 128 (also known as drilling “mud”) stored in a pit 130. The pit 130 may be formed adjacent to the wellsite 100, as shown, in which a pump 132 may be used to pump the drilling fluid 128 into the wellbore 114. In this embodiment, the pump 132 may pump and deliver the drilling fluid 128 into and through a port of the rotary swivel 126, thereby enabling the drilling fluid 128 to flow into and downwardly through the drill string 112, the flow of the drilling fluid 128 indicated generally by direction arrow 134. This drilling fluid 128 may then exit the drill string 112 through one or more ports disposed within and/or fluidly connected to the drill string 112. For example, in this embodiment, the drilling fluid 128 may exit the drill string 112 through one or more ports formed within the drill bit 116.

As such, the drilling fluid 128 may flow back upwardly through the borehole 114, such as through an annulus 136 formed between the exterior of the drill string 112 and the interior of the borehole 114, the flow of the drilling fluid 128 indicated generally by direction arrow 138. With the drilling fluid 128 following the flow pattern of direction arrows 134 and 138, the drilling fluid 128 may be able to lubricate the drill string 112 and the drill bit 116, and/or may be able to carry formation cuttings formed by the drill bit 116 (or formed by any other drilling components disposed within the borehole 114) back to the surface of the wellsite 100. As such, this drilling fluid 128 may be filtered and cleaned and/or returned back to the pit 130 for recirculation within the borehole 114.

Though not shown in this embodiment, the drill string 112 may further include one or more stabilizing collars. A stabilizing collar may be disposed within and/or connected to the drill string 112, in which the stabilizing collar may be used to engage and apply a force against the wall of the borehole 114. This may enable the stabilizing collar to prevent the drill string 112 from deviating from the desired direction for the borehole 114. For example, during drilling, the drill string 112 may “wobble” within the borehole 114, thereby enabling the drill string 112 to deviate from the desired direction of the borehole 114. This wobble may also be detrimental to the drill string 112, components disposed therein, and the drill bit 116 connected thereto. However, a stabilizing collar may be used to minimize, if not overcome altogether, the wobble action of the drill string 112, thereby possibly increasing the efficiency of the drilling performed at the wellsite 100 and/or increasing the overall life of the components at the wellsite 100.

As discussed above, the drill string 112 may include a bottom hole assembly 118, such as by having the bottom hole assembly 118 disposed adjacent to the drill bit 116 within the drill string 112. The bottom hole assembly 118 may include one or more components included therein, such as components to measure, process, and store information. Further, the bottom hole assembly 118 may include components to communicate and relay information to the surface of the wellsite.

As such, in this embodiment shown in FIG. 1, the bottom hole assembly 118 may include one or more logging-while-drilling (“LWD”) tools 140 and/or one or more measuring-while-drilling (“MWD”) tools 142. Further, the bottom hole assembly 118 may also include a steering-while-drilling system (e.g., a rotary-steerable system) and motor 144, in which the rotary-steerable system and motor 144 may be coupled to the drill bit 116.

The LWD tool 140 shown in FIG. 1 may include a thick-walled housing, commonly referred to as a drill collar, and may include one or more of a number of logging tools known in the art. Thus, the LWD tool 140 may be capable of measuring, processing, and/or storing information therein, as well as capabilities for communicating with equipment disposed at the surface of the wellsite 100.

Further, the MWD tool 142 may also include a housing (e.g., drill collar), and may include one or more of a number of measuring tools known in the art, such as tools used to measure characteristics of the drill string 112 and/or the drill bit 116. The MWD tool 142 may also include an apparatus for generating and distributing power within the bottom hole assembly 118. For example, a mud turbine generator powered by flowing drilling fluid therethrough may be disposed within the MWD tool 142. Alternatively, other power generating sources and/or power storing sources (e.g., a battery) may be disposed within the MWD tool 142 to provide power within the bottom hole assembly 118. As such, the MWD tool 142 may include one or more of the following measuring tools: a weight-on-bit measuring device, a torque measuring device, a vibration measuring device, a shock measuring device, a stick slip measuring device, a direction measuring device, an inclination measuring device, and/or any other device known in the art used within an MWD tool.

Referring now to FIG. 2, a side view of a tool 200 in accordance with one or more embodiments of the present disclosure is shown. The tool 200 may be connected to and/or included within a drill string 202, in which the tool 200 may be disposed within a borehole 204 formed within a subsurface formation F. As such, the tool 200 may be included and used within a bottom hole assembly, as described above.

Particularly, in this embodiment, the tool 200 may include a sampling-while drilling (“SWD”) tool, such as that described within U.S. Pat. No. 7,114,562, filed on Nov. 24, 2003, entitled “Apparatus and Method for Acquiring Information While Drilling,” and incorporated herein by reference in its entirety. As such, the tool 200 may include a probe 210 to hydraulically establish communication with the formation F and draw formation fluid 212 into the tool 200.

In this embodiment, the tool 200 may also include a stabilizer blade 214 and/or one or more pistons 216. As such, the probe 210 may be disposed on the stabilizer blade 214 and extend therefrom to engage the wall of the borehole 204. The pistons, if present, may also extend from the tool 200 to assist probe 210 in engaging with the wall of the borehole 204. In alternative embodiments, though, the probe 210 may not necessarily engage the wall of the borehole 204 when drawing fluid.

As such, fluid 212 drawn into the tool 200 may be measured to determine one or more parameters of the formation F, such as pressure and/or pretest parameters of the formation F. Additionally, the tool 200 may include one or more devices, such as sample chambers or sample bottles, that may be used to collect formation fluid samples. These formation fluid samples may be retrieved back at the surface with the tool 200. Alternatively, rather than collecting formation fluid samples, the formation fluid 212 received within the tool 200 may be circulated back out into the formation F and/or borehole 204. As such, a pumping system may be included within the tool 200 to pump the formation fluid 212 circulating within the tool 200. For example, the pumping system may be used to pump formation fluid 212 from the probe 210 to the sample bottles and/or back into the formation F. Alternatively still, in one or more embodiments, rather than collecting formation fluid samples, a tool in accordance with embodiments disclosed herein may be used to collect samples from the formation F, such as one or more coring samples from the wall of the borehole 204.

Referring now to FIG. 3, a schematic view of a tool 300 in accordance with one or more embodiments of the present disclosure is shown. The tool 300 may be connected to and/or included within a bottom hole assembly, in which the tool 300 may be disposed within a borehole 304 formed within a subsurface formation F.

In this embodiment, the tool 300 may be a pressure LWD tool used to measure one or more downhole pressures, including annular pressure, formation pressure, and pore pressure, before, during, and/or after a drilling operation. Further, those having ordinary skill in the art will appreciate that other pressure LWD tools may also be utilized in one or more embodiments, such as that described within U.S. Pat. No. 6,986,282, filed on Feb. 18, 2003, entitled “Method and Apparatus for Determining Downhole Pressures During a Drilling Operation,” and incorporated herein by reference.

As shown, the tool 300 may be formed as a modified stabilizer collar 310, similar to a stabilizer collar as described above, and may have a passage 312 formed therethrough for drilling fluid. The flow of the drilling fluid through the tool 300 may create an internal pressure P₁, and the exterior of the tool 300 may be exposed to an annular pressure P_(A) of the surrounding borehole 304 and formation F. A differential pressure P_(δ) formed between the internal pressure P₁ and the annular pressure P_(A) may then be used to activate one or more pressure devices 316 included within the tool 300.

In this particular embodiment, the tool 300 includes two pressure measuring devices 316A and 316B that may be disposed on stabilizer blades 318 formed on the stabilizer collar 310. The pressure measuring device 316A may be used to measure the annular pressure P_(A) in the borehole 304, and/or may be used to measure the pressure of the formation F when positioned in engagement with a wall 306 of the borehole 304. As shown in FIG. 3, the pressure measuring device 316A is not in engagement with the borehole wall 306, thereby enabling the pressure measuring device 316A to measure the annular pressure P_(A), if desired. However, when the pressure measuring device 316A is moved into engagement with the borehole wall 306, the pressure measuring device 316A may be used to measure pore pressure of the formation F.

As also shown in FIG. 3, the pressure measuring device 316B may be extendable from the stabilizer blade 318, such as by using a hydraulic control disposed within the tool 300. When extended from the stabilizer blade 318, the pressure measuring device 316B may establish sealing engagement with the wall 306 of the borehole 304 and/or a mudcake 308 of the borehole 304. This may enable the pressure measuring device 316B to take measurements of the formation F also. Other controllers and circuitry, not shown, may be used to couple the pressure measuring devices 316 and/or other components of the tool 300 to a processor and/or a controller. This processor and/or controller may then be used to communicate the measurements from the tool 300 to other tools within a bottom hole assembly or to the surface of a wellsite. As such, a pumping system may be included within the tool 300, such as including the pumping system within one or more of the pressure devices 316 for activation and/or movement of the pressure devices 316.

Referring now to FIG. 4, a side view of a tool 400 in accordance with one or more embodiments of the present disclosure is shown. In this embodiment, the tool 400 may be a “wireline” tool, in which the tool 400 may be suspended within a borehole 404 formed within a subsurface formation F. As such, the tool 400 may be suspended from an end of a multi-conductor cable 406 located at the surface of the formation F, such as by having the multi-conductor cable 406 spooled around a winch (not shown) disposed on the surface of the formation F. The multi-conductor cable 406 is then couples the tool 400 with an electronics and processing system 408 disposed on the surface.

The tool 400 shown in this embodiment may have an elongated body 410 that includes a formation tester 412 disposed therein. The formation tester 412 may include an extendable probe 414 and an extendable anchoring member 416, in which the probe 414 and anchoring member 416 may be disposed on opposite sides of the body 410. One or more other components 418, such as a measuring device, may also be included within the tool 400.

The probe 414 may be included within the tool 400 such that the probe 414 may be able to extend from the body 410 and then selectively seal off and/or isolate selected portions of the wall of the borehole 404. This may enable the probe 414 to establish pressure and/or fluid communication with the formation F to draw fluid samples from the formation F. The tool 400 may also include a fluid analysis tester 420 that is in fluid communication with the probe 414, thereby enabling the fluid analysis tester 420 to measure one or more properties of the fluid. The fluid from the probe 414 may also be sent to one or more sample chambers or bottles 422, which may receive and retain fluids obtained from the formation F for subsequent testing after being received at the surface. The fluid from the probe 414 may also be sent back out into the borehole 404 or formation F.

Referring now to FIG. 5, a side view of another tool 500 in accordance with one or more embodiments of the present disclosure is shown. Similar to the above embodiment in FIG. 4, the tool 500 may be suspended within a borehole 504 formed within a subsurface formation F using a multi-conductor cable 506. In this embodiment, the multi-conductor cable 506 may be supported by a drilling rig 502.

As shown in this embodiment, the tool 500 may include one or more packers 508 that may be configured to inflate, thereby selectively sealing off a portion of the borehole 504 for the tool 500. Further, to test the formation F, the tool 500 may include one or more probes 510, and the tool 500 may also include one or more outlets 512 that may be used to inject fluids within the sealed portion established by the packers 508 between the tool 500 and the formation F.

Referring now to FIG. 6, a side view of a wellsite 600 having a drilling rig 610 in accordance with one or more embodiments of the present disclosure is shown. In this embodiment, a borehole 614 may be formed within a subsurface formation F, such as by using a drilling assembly, or any other method known in the art. Further, in this embodiment, a wired pipe string 612 may be suspended from the drilling rig 610. The wired pipe string 612 may be extended into the borehole 614 by threadably coupling multiple segments 620 (i.e., joints) of wired drill pipe together in an end-to-end fashion. As such, the wired drill pipe segments 620 may be similar to that as described within U.S. Pat. No. 6,641,434, filed on May 31, 2002, entitled “Wired Pipe Joint with Current-Loop Inductive Couplers,” and incorporated herein by reference.

Wired drill pipe may be structurally similar to that of typical drill pipe, however the wired drill pipe may additionally include a cable installed therein to enable communication through the wired drill pipe. The cable installed within the wired drill pipe may be any type of cable capable of transmitting data and/or signals therethrough, such an electrically conductive wire, a coaxial cable, an optical fiber cable, and or any other cable known in the art. Further, the wired drill pipe may include having a form of signal coupling, such as having inductive coupling, to communicate data and/or signals between adjacent pipe segments assembled together.

As such, the wired pipe string 612 may include one or more tools 622 and/or instruments disposed within the pipe string 612. For example, as shown in FIG. 6, a string of multiple borehole tools 622 may be coupled to a lower end of the wired pipe string 612. The tools 622 may include one or more tools used within wireline applications, may include one or more LWD tools, may include one or more formation evaluation or sampling tools, and/or may include any other tools capable of measuring a characteristic of the formation F.

The tools 622 may be connected to the wired pipe string 612 during drilling the borehole 614, or, if desired, the tools 622 may be installed after drilling the borehole 614. If installed after drilling the borehole 614, the wired pipe string 612 may be brought to the surface to install the tools 622, or, alternatively, the tools 622 may be connected or positioned within the wired pipe string 612 using other methods, such as by pumping or otherwise moving the tools 622 down the wired pipe string 612 while still within the borehole 614. The tools 622 may then be positioned within the borehole 614, as desired, through the selective movement of the wired pipe string 612, in which the tools 622 may gather measurements and data. These measurements and data from the tools 622 may then be transmitted to the surface of the borehole 614 using the cable within the wired drill pipe 612.

As such, a coring tool, and one or more methods of using a coring tool, in accordance with the present disclosure may be included within one or more of the embodiments shown in FIGS. 1-6, in addition to being included within other tools and/or devices that may be disposed downhole within a formation. The coring tool, thus, may be used to extract one or more coring samples from the borehole of a formation. The coring tool may be an axial coring tool and/or a sidewall coring tool, in which the coring tool includes a coring bit that may be used to extract a coring sample from the wall of the borehole. As shown in the following figures, only a sidewall coring tool is shown. However, those having ordinary skill in the art will appreciate that other coring tools may also be included within one or more embodiments with departing from the scope of the present disclosure.

A coring tool in accordance with one or more embodiments of the present disclosure may include, at least, a coring bit movably attached to the coring tool. For example, the coring bit may be able to extend and retract from the coring tool such that the coring bit may be able to be received within a wall of a borehole. Further, the coring bit may be able to rotate with respect to the coring tool, such as when the coring bit is extended from the coring tool. This may enable the coring bit to drill into and collect a coring sample from the wall of the borehole when disposed downhole. Furthermore, the coring bit may be able to rotate with respect to the coring tool, such as by having the coring bit rotate between positions when disposed within the coring tool. For example, the coring bit may further be able to rotate between a coring position and an ejection position within the coring tool.

The coring tool may further include a handling piston disposed therein, in which the handling piston may also be movably disposed within the coring tool. For example, the handling piston may be able to move between multiple positions, such as move between a retracted position and an extended position. When moving between positions, the coring bit may be disposed within the ejection position. As such, the handling piston may be able to move from the retracted position, through the coring bit, and into an extended position.

Such movement of the handling piston may enable the handling piston to determine the presence and/or length of a coring sample if a coring sample has been successfully drilled from a borehole wall and received into the coring tool with the coring bit. For example, as the handling piston moves through the coring bit, the handling piston may push a coring sample out of the coring bit, if such a coring sample is present within the coring bit of the coring tool. The handling piston may then push the coring sample into a coring sample holder, for example, disposed within the coring tool. As the handling piston moves through the coring bit and into an extended position, the handling piston may then engage the top of the coring sample, if such a coring sample is present within the coring tool, or the handling piston may engage the inner bottom of the coring sample holder, if such a coring sample is not present within the coring tool.

As such, the distance of the movement of the handling piston between the retracted position and the extended position may be measured. Such a measurement of the distance of movement of the handling piston may then enable the presence and/or length of a coring sample to be determined. If a coring sample is determined to be present within the coring tool, the coring sample may then be stored within a storage area of the coring tool. On the other hand, if a coring sample is determined to not be present within the coring tool, the coring tool may then re-drill into the wall of the borehole for another attempt to successfully retrieve a coring sample from the formation, and thus avoid having to store an empty sample holder into the storage area of the coring tool. As such, the present disclosure contemplates one or more methods to drill within a borehole with a coring tool and/or one or more methods to detect the presence and/or determine the length of a coring sample within a coring tool.

Referring now to FIGS. 7A and 7B, multiple views of a coring tool 721 in accordance with one or more embodiments of the present disclosure are shown. Particularly, in FIG. 7A, a side view of a wireline tool 701 is shown, in which the wireline tool 701 may include the coring tool 721. Further, FIG. 7B shows a perspective view of the coring tool 721.

In this embodiment, the tool 701 may be suspended within a borehole 705 formed within a subsurface formation F, in which the tool 701 may be suspended from an end of a multi-conductor cable 707 located at the surface of the formation F. As such, the cable 707 may enable the wireline tool 701 and the coring tool 721 to be electrically coupled to a surface unit 709, in which the surface unit 709 may further include a control panel 711 and/or a monitor 713. The surface unit 709 may be able to provide electrical power to the coring tool 721, such as to monitor the status of the downhole coring and other activities of downhole equipment with the tool 701, in addition to being able to control the activities of the coring tool 721 and other downhole equipment with the tool 701.

As shown, the coring tool 721 may be disposed within an elongate housing of the wireline tool 701 such that the coring tool 721 may be disposed downhole within the borehole 705. The coring tool 721 may include a coring assembly 723, which may include one or more motors 725 that may be powered, for example, through the use of the power provided from the cable 707. The coring tool 721 may further include a coring bit 727, in which the coring bit 727 may have an open end 729 for cutting into the formation F and receiving a coring sample. Further, the coring tool 721 may be able to extend and retract the coring bit 727 into and out of the coring tool 721, and may also be able to rotate the coring bit 727 against the wall of the borehole 705.

FIGS. 7A and 7B show the coring tool 721 in the coring position, in which the coring tool 721 is used to drill into the wall of the borehole 705 and receive a coring sample. Particularly, the coring bit 727 may be rotated by the motor 725, in which the coring bit 727 receives the coring sample into the coring bit 727 through the open end 729. The coring bit 727 may then be retracted within the coring assembly 723, in which the coring sample may be stored within a storage area (discussed more below) of the coring tool 721.

As shown, the tool 701 may include one or more pistons 703 (e.g., anchoring shoes) that may be able to extend from the housing of the tool 701 and engage the wall of the borehole 705. As such, this may enable the pistons 703 to provide stability to the tool 701 and coring tool 721, particularly when the coring tool 721 is drilling into the formation F. Further, the coring tool 721 may include at least two motors, in which one motor may be used to rotate and apply torque to the coring bit 727, and the other may be used to extend/retract and apply weight on the coring bit 727. Further, though the embodiments shown in FIGS. 7A and 7B show the cable 707 used to provide power to the coring tool 721, those having ordinary skill in the art will appreciate that other methods may be used to provide power to a coring tool, such as by the use of a battery, a power cell, and/or an electrically charged accumulator disposed downhole. Furthermore, a coring tool in accordance with embodiments disclosed herein may be included within one or more other embodiments, such as within one of the embodiments shown within FIGS. 1-6.

Referring now to FIG. 8, a schematic view of a coring tool 821 in accordance with one or more embodiments of the present disclosure is shown. As with the above embodiment, the coring tool 821 includes a coring assembly 823 with a coring motor 825, and further includes a coring bit 827 operatively coupled to the motor 825. As such, the motor 825 may be able to drive the coring bit 827 such that the coring bit 827 may be able to drill into the formation (e.g., wall of a borehole) and obtain a coring sample.

When driving the coring bit 827 into the formation, the coring bit 827 may be pressed against and into the formation while also being rotated. Thus, the coring tool 821 may apply a weight-on-bit (“WOB”) (e.g., a force that presses the coring bit 827 into the formation) and a torque on the coring bit 827. As such, and as shown in FIG. 8, the WOB applied to the coring bit 827 may be generated by a motor 831, in which the motor 831 may be an AC motor, a brushless DC motor, and/or any other power source, and a control assembly 833. As shown, the control assembly 833 may include a hydraulic pump 834, a valve 835, such as a feedback flow control valve, and a piston 836. In such an embodiment, the motor 831 may be used to supply power to the hydraulic pump 834, in which the flow of hydraulic fluid from the pump 834 may be controlled and/or regulated by the valve 835. Pressure then from the hydraulic fluid from the pump 834 may be used to drive the piston 836, in which the piston 836 may be used to apply a WOB upon the coring bit 827.

Further, in one or more embodiments, torque for the coring bit 827 may be supplied by another motor 837, in which the motor 837 may also be an AC motor, a brushless DC motor, and/or any other power source, and a gear pump 839. The motor 837 may be used to drive the gear pump 839, in which the gear pump 839 may be used to supply a flow of hydraulic fluid to the coring motor 825. As such, the coring motor 825, which thus may be a hydraulic coring motor, may impart a torque to the coring bit 827 that enables the coring bit 827 to rotate.

Those having ordinary skill in the art will appreciate that, in addition to the above embodiments shown and described above with respect to a coring tool, other arrangements and mechanisms may be used to apply such forces as WOB and torque to a coring bit without departing from the scope of the present disclosure. As such, additional examples of mechanisms that may be used to apply WOB and torque within a coring tool are disclosed within U.S. Pat. Nos. 6,371,221 and 7,191,831, both of which are assigned to the assignee of the present application and are incorporated herein by reference in their entirety.

Referring now to FIGS. 9A-9D, multiple side views of a coring tool 921 in accordance with one or more embodiments of the present disclosure are shown. As with the above embodiments, the coring tool 921 includes a coring assembly 923 with a motor 925, and further includes a coring bit 927 operatively coupled to the motor 925. Further, the motor 925 may be able to drive the coring bit 927 such that the coring bit 927 may be able to drill into the formation (e.g., wall of a borehole) and obtain a coring sample. As such, the coring assembly 923 may include the motor 925, in which the coring bit 927 may be able to slide axially and rotate with respect to the coring assembly 923. Thus, FIGS. 9A-9D show the coring bit 927 disposed within different positions with respect to the coring tool 921 (discussed more below).

As shown in this embodiment, the coring tool 921 includes a tool housing 941 extending along a longitudinal axis 900 of the tool 921. In one or more embodiments, the tool housing 941 may have a coring aperture 943 formed therein, in which coring samples may be received through the coring aperture 943. Further, as shown, the coring assembly 923 may be disposed within the tool housing 941, in addition to a storage area 961 disposed within the tool housing 941.

Further, as discussed above, the coring bit 927 may disposed within the coring tool 921 such that the coring bit 927 is movable between multiple positions with respect to the coring tool 921. As such, in one embodiment, one or more rotation link arms 945 and/or one or more rotation pistons 947 may be provided within the coring tool 921 for rotatably mounting the coring assembly 923, and the coring bit 927 coupled thereto, within the coring tool 921. For example, as shown in FIGS. 9A-9D, the rotation link arms 945 may be pivotably coupled to the coring assembly 923, in which the rotation pistons 947 may be mounted within the tool housing 941 and pivotably coupled to the rotation link arms 945. As such, one or more of the pistons 947 may be actuated to extend and/or retract, in which the movement of the pistons 947 may be transferred to the rotation link arms 945 to correspondingly move (e.g., rotate) the coring assembly 923. As used herein, the terms “pivotably coupled” or “pivotably connected” may mean a connection between two tool components that allows relative rotating or pivoting movement of one of the components with respect to the other component, but does not allow sliding or translational movement of the one component with respect to the other.

For example, by extending the rotation piston 947A, this movement may correspondingly enable the rotation link arms 945 to rotate the coring assembly 923 and the coring bit 927 in the counter-clockwise direction, such as shown in a movement from FIG. 9B to FIG. 9A. Similarly, by extending the rotation the piston 947B and retracting the piston 947A, this movement may correspondingly enable the rotation link arms 945 to rotate the coring assembly 923 and the coring bit 927 in the clockwise direction, such as shown in a movement from FIG. 9A to FIG. 9B. Thus, this arrangement may enable the coring bit 927 to be movable between multiple positions with respect to the coring tool 921.

Those having ordinary skill in the art will appreciate that, in addition to the above embodiments shown and described above with respect to a coring tool, other arrangements and mechanisms may be used to enable a coring assembly and/or a coring bit to move between multiple positions within a coring tool without departing from the scope of the present disclosure. Additional examples of mechanisms that may be used within a coring tool are disclosed within US. Patent Publication No. 2009/0114447, which is assigned to the assignee of the present application and is incorporated herein by reference in their entirety.

As mentioned above, the coring assembly 923 and/or the coring bit 927 may be able to move between multiple positions within the coring tool 921. Accordingly, in accordance with one or more embodiments of the present disclosure, the coring assembly 923 and/or the coring bit 927 may be able to move between a coring position and an ejection position. In the coring position, the coring bit 927 may be disposed substantially perpendicular to the longitudinal axis 900 of the coring tool 921. FIGS. 9B-9D show examples of the coring bit 927 disposed in the coring position. Further, in the ejection position, the coring bit 927 may be disposed substantially parallel to the longitudinal axis 900 of the coring tool 921. FIG. 9A shows an example of the coring bit 927 disposed in the ejection position.

When the coring bit 927 is in the coring position, the coring bit 927 may be able to extend and retract from the coring tool 921, such as shown through the movement of the coring bit 927 in FIGS. 9B-9D. As such, in one or more embodiments, in the coring position, the open end of the coring bit 927 may register with the coring aperture 943 of the tool housing 941, and conversely in the ejection position, the open end of the coring bit 927 may register with the storage area 961. As used herein, the term “register” may be used to indicate that voids or spaces defined by two components, such as the open end of the coring bit and the storage area and/or the coring aperture, may be substantially aligned with each other.

Referring still to FIGS. 9A-9D, the coring tool 921 may include a system to handle and/or store one or more coring samples. As such, and as mentioned above, the coring tool 921 may include the storage area 961. In this embodiment, the storage area 961 may include a coring sample receptacle 963, in which the coring sample receptacle 963 may include at least two storage columns 965 and 967. The storage columns 965 and 967 may each be sized to receive one or more coring sample holders 969, such as one or more canisters, in which the coring sample holders 969 may be adapted to receive and hold coring samples. As shown particularly in FIGS. 9A-9D, each storage column 965 and 967 may be sized to receive six coring sample holders 969. However, those having ordinary skill in the art will appreciate that the present application is not so limited, as the storage columns may be sized to hold more or less than six coring sample holders. For example, in one embodiment, the storage columns may be sized to hold twenty five coring sample holders. Further, as shown, the coring sample receptacle 963 may have a proximal end 971 positioned closer to the coring bit 927 and a distal end 973 positioned farther from the coring bit 927.

The storage area 961 may include one or more shifters 975 and 977 included therewith, in which the shifters 975 and 977 may be able to move the coring sample holders 969 between the storage columns 965 and 967. For example, as shown in FIGS. 9A-9D, the shifter 975 may be coupled to the proximal end 971 and may include fingers, for example, adapted to grip an exterior of the coring sample holders 969. The shifter 975 may be mounted on a spindle 979, in which the shifter 975 may be able to rotate from a first position, in which the shifter 975 registers with the proximal end 971 of the first storage column 965, to a second position, in which the shifter 975 registers with the proximal end 971 of the second storage column 967. Similarly, the second shifter 977 may be coupled to the distal end 973 and may similarly rotate between a first position, in which the shifter 977 registers with the distal end 973 of the first storage column 965, and a second position, in which the shifter 977 registers with the distal end 973 of the second storage column 967.

The coring tool 921 may further include one or more transporters to assist in moving the coring sample holders 969. As such, a first transporter may be provided for transferring an empty coring sample holder 969 (not having a coring sample disposed therein) from the shifter 975 up to and into the coring bit 927 as the first transporter moves from an extended position to a retracted position. For example, in the embodiment shown in FIGS. 9A-9D, the first transporter may include a handling piston 981, such as a ball-screw piston, in which the handling piston 981 may be disposed substantially coaxial with respect to the first storage column 965. Further, the handling piston 981 may be disposed substantially coaxial with the coring bit 927 when the coring bit 927 is disposed within the ejection position, as shown in FIG. 9A.

A core transfer tube 991 may be included within the coring tool 921, in which the core transfer tube 991 may be disposed between the coring bit 927 and the shifter 975. The core transfer tube 991 may thereby facilitate the transfer of a coring sampler holder 969 between the coring bit 927 and the shifter 975. The handling piston 981 may include a gripper, such as gripper brush 985, in which the gripper may be adapted to engage an interior surface of a coring sample holder 969. Accordingly, the handling piston 981 may extend into and through the coring bit 927 as the handling piston 981 moves to an extended position. The gripper brush 985 may be disposed at the end of the handling piston 981 and may further be used to hold the coring sample holder 969 as the coring sample holder 969 is transferred from the shifter 975 to the coring bit 927.

As such, the coring bit 927 may be configured to retain a coring sample and/or coring sample holder 969 within the coring bit 927 until the coring sample holder 969 is to be discharged from the coring bit 927. Examples regarding one or more coring bits that may be used within one or more embodiments of the present disclosure are disclosed within U.S. Patent Application Publication No. 2005/0133267 A1, which is incorporated herein by reference in its entirety.

The handling piston 981 may also be used to advance a coring sample holder 969 from the coring bit 927 to the shifter 975 and/or to the proximal end 971 of the first storage column 965. As shown in FIGS. 9A-9D, the handling piston 981 may include a foot 983 that is adapted to engage a coring sample and/or the inner diameter of the coring sample holder 969. The handling piston 981 may be actuated to an extended position, in which the handling piston 981 may pass through the coring bit 927 and/or through the proximal shifter 975 and partially into the proximal end 971 of the first storage column 965. This movement may enable the coring sample holder 969 to be transported from the coring bit 927 to the shifter 975 and/or to the first storage column 965. A coring sample holder 969 disposed inside the coring bit 927 and having a recently obtained coring sample disposed therein may, thus, be transferred from the coring bit 927 to the shifter 975 and/or the first storage column 965 by the handling piston 981.

In another embodiment (not shown), the handling piston 981 may be used to transfer an empty coring sample holder 969 from the shifter 975 up to and into the transfer tube 991, in which the coring sample holder 969 may be secured within the transfer tube 991. A collet, a retaining pin, and/or other retention device, may then be disposed inside the transfer tube 991 to retain the coring sample holder 969 within the upper end of the transfer tube 991 and not be further transported by the handling piston 981. In such an embodiment, the handling piston 981 may also then be used to advance a coring sample from the coring bit 927 into the coring sample holder 969 secured in the transfer tube 991. As such, the handling piston 981 may further be used to transfer the coring sample holder 969 disposed inside the transfer tube 991, the coring sample holder 969 holding a recently obtained coring sample from the coring bit 927, from the transfer tube 991 to the shifter 975 and/or the first storage column 965 using the handling piston 981. Further, in this embodiment, as a coring sample holder is not provided within the coring bit 927, the coring bit 927 may include a non-rotating coring sleeve for receiving the coring sample.

Further, a second transporter may be included within the coring tool 921, such as lift piston 987, in which the lift piston 987 may be used to advance a coring sample holder 969 from the shifter 977 to the second storage column 967. As shown in FIGS. 9A-9D, the lift piston 987 may be disposed coaxially with the second storage column 987, in which the lift piston 987 may be adapted to move from a retracted position to an extended position. With such movement, the lift piston 987 may be able to pass through the shifter 977 and partially into the second storage column 967. As the lift piston 987 moves into the extended position, the lift piston 987 may transport a coring sample holder 969 disposed inside the shifter 977 into the distal end 973 of the second storage column 967.

As such, during operation, the coring tool 921 may be used to transfer one or more coring samples between the storage area 961 and the coring bit 927, and may further store the coring sample holders 969 with the storage columns 965 and 967. Prior to obtaining a first coring sample, the first and second storage columns 965 and 967 of the receptacle 963 may contain empty coring sample holders 969.

These coring sample holders 969 may include a first coring sample holder 969A positioned at the proximal end 971 of the first storage column 965, a second coring sample holder 969B positioned at a distal end 973 of the first storage column 965, a third coring sample holder 969C positioned at a distal end 973 of the second storage column 967, and a fourth coring sample holder 969D positioned at a proximal end 971 of the second storage column 967. Further, an additional coring sample holder 969 may be disposed within the coring bit 927 and/or the transfer tube 991, in which the coring sample holder 969 may be adapted to receive the first coring sample formed therein.

The coring bit 927 may then be operated to drill and obtain a coring sample from the wall of a borehole, in which the coring sample may be disposed within the coring sample holder 969. If the coring bit 927 has the coring sample holder 969 disposed therein, the coring sample may be received within the coring sample holder 969 while the coring bit 927 and the coring assembly 923 is disposed within the coring position. If the coring sample holder 969 is instead within the transfer tube 991, the coring bit 927 may be rotated into the ejection position and the handling piston 981 may be moved from the retracted position into the extended position to have the coring sample inside the coring bit 927 transported and disposed within the coring sample holder 969 retained by the transfer tube 991.

The handling piston 981 may then be further extended within the extended position such that the handling piston 981 transports the current coring sample holder 969 to the receptacle 963 such that the current coring sample holder 969 may be disposed adjacent the proximal end 971 of the first storage column 965. Still, further extension of the handling piston 981 may insert the current coring sample holder 969 in the first storage column 965 such that the coring sample holder 969 engages with the first coring sample holder 969A. This engagement may advance the first series of stacked coring sample holders 969 in the first storage column 965 to eject the second coring sample holder 969B from the distal end 973 thereof. As such, the shifter 977 may be positioned to register with the first storage column 965, thereby enabling the shifter 977 to receive the ejected coring sample holder 969B.

The shifter 977 may then be rotated to register with the second storage column 967, in which the lift piston 987 may be extended to insert the second coring sample holder 969B into the second storage column 967. As the second coring sample holder 969B is inserted into the second storage column 967, the entire second series of stacked coring sample holders 969 may advanced in a direction along the second storage column 967, thereby ejecting the fourth coring sample holder 969D from the proximal end 971 of the second storage column 967. As such, the shifter 975 may be positioned to register with the second storage column 967, thereby enabling the shifter 975 to receive the ejected fourth coring sample holder 969D. By this time, the handling piston 981 may be at least partially retracted such that the handling piston 981 may be clear of the shifter 975. The shifter 975 may then rotate to register with the first storage column 965, thereby transferring the fourth coring sample holder 969D to be positioned adjacent the proximal end 971 of the first storage column 965.

The handling piston 981 may then again be extended until the gripper 985 engages the fourth coring sample holder 969D. The handling piston 981 may then be retracted to transfer the fourth coring sample holder 969D from the receptacle 963 to the transfer tube 991 and/or the coring bit 927. If received within the coring bit 927, the fourth coring sample holder 969D may be disengaged from the handling piston 981 as the handling piston 981 retracts through the coring bit 927, thereby enabling the fourth coring sample holder 969D to remain inside the coring bit 927 to receive the next coring sample. If received within the transfer tube 991, the fourth coring sample holder 969D may be disengaged from the handling piston 981 as the handling piston 981 retracts through the transfer tube 991, thereby enabling the fourth coring sample holder 969D to remain inside the transfer tube 991 to receive the next coring sample.

The above steps may be repeated until each coring sample holder contains a coring sample therein. The coring sample holders with coring samples may be stored in order inside the receptacle 963, with the oldest or first coring sample ultimately being located at the proximal end 971 of the second storage column 969 and the last or most recent coring sample being located at the proximal end 971 of the first storage column 965. While one method of handling and storing cores is shown and described herein, those having ordinary skill in the art may appreciate that additional methods of handling/storing coring samples may be used in one or more embodiments disclosed herein without departing from the scope of this disclosure.

A coring tool in accordance with one or more embodiments disclosed herein may include one or more sensors for detecting the presence and/or geophysical properties of coring samples obtained from the formation. For example, the tool 921 may include a geophysical-property measuring unit that may connected by a bus of the coring tool 921 to a telemetry unit, thereby enabling the coring tool 921 to transmit data to a data acquisition and processing apparatus located at the surface. The geophysical-property measuring unit may be a gamma-ray detection unit, NMR sensors, electromagnetic sensor, and/or any other device known in the art. Additional details regarding the geophysical-property measuring unit are provided in U.S. Patent Application Publication No. 2007/0137894 in the name of Fujisawa et al., which is incorporated herein by reference in its entirety.

As such, in accordance with one or more embodiments disclosed herein, a coring tool in accordance with embodiments disclosed herein may enable the coring tool to detect the presence of a coring sample within a coring tool, in addition to measuring the length of the coring sample obtained from the formation if such a coring sample is present within the coring tool.

For example, with reference to FIG. 10, in which a schematic view of a coring tool 1021 in accordance with one or more embodiments of the present disclosure is shown, a first position (retracted position) of the handling piston 1081 may be obtained during the course of operation of the coring tool 1021. The coring bit (not shown in this embodiment) may be disposed also within a first position (coring position), in which the coring bit is operated to retrieve a coring sample, as described above. Subsequently, the coring bit may be moved from the first position to a second position (ejection position), such as by rotating the coring bit from the coring position to the ejection position. The handling piston 1081 may then be extended from the retracted position to an extended position, in which this movement will eject the coring sample from the coring bit. A coring sample holder 1069 may also be disposed within the coring bit with the coring sample, in which the handling piston 1081 may also eject the coring sample holder 1069 from the coring bit. The handling piston 1081 may then continue to extend such that the coring sample and the coring sample holder 1069 is disposed within a transfer tube and/or a shifter, as discussed above. Otherwise, as the coring sample is ejected from the coring bit, the coring sample may be received by the coring sample holder 1069 disposed in a coaxial alignment with the coring bit within a transfer tube and/or a shifter.

Further, as shown in FIG. 10, a retaining mechanism 1099 may be included within the coring tool 1021, in which the retaining mechanism 1099 may be disposed within or adjacent to a transfer tube and/or a shifter of the coring tool 1021, if such components are included within the coring tool 1021. The retaining mechanism 1099 may be configured to hold the coring sample holder 1069A at a desired location within the coring tool 1021, such as at a desired location within a transfer tube and/or a shifter. The retaining mechanism 1099 may include a collet, a retaining pin, and/or any other retaining mechanism known in the art. As such, the retaining mechanism 1099 may be selectively activated to retain the coring sample holder 1069A. For example, the retaining mechanism 1099 may be selectively activated, thereby extending the retaining mechanism 1099, or a portion thereof, to retain the coring sample holder 1069A, and may be selectively de-activated, thereby retracting the retaining mechanism 1099, or a portion thereof, to no longer retain the coring sample holder 1069A. Further, when activated, the retaining mechanism 1099 may prevent the coring sample holder 1069A from any undesired movement, such as by preventing the coring sample holder 1069A from movement, particularly when the handling piston 1081 extends to engage the coring sample holder 1069A. When de-activated, the retaining mechanism 1099 may enable the coring sample holder 1069A to be disposed and stored within the storage area 1061 of the coring tool 1021.

As such, as the handling piston 1081 extends, the handling piston 1081 may engage the coring sample disposed within the coring sample holder 1069, if such a coring sample is present within the coring sample holder 1069, or the handling piston 1081 may engage the bottom surface of the coring sample holder 1069 (or some other known object or surface not the coring sample), if such a coring sample is not present within the coring sample holder 1069. For example, the coring bit may not be successful when attempting to obtain a coring sample from the formation. As such, if the coring bit is not successful when attempting to obtain a coring sample from the formation, a coring sample may not be present within the coring tool 1021, particularly as the handling piston 1081 extends downward to engage the upper surface of the coring sample within the coring sample holder 1069. Thus, in one or more embodiments of the present disclosure, the handling piston 1081 may extend to a second position (extended position), in which the handling piston 1081 may engage either the upper surface of the coring sample, if a coring sample is present, or may engage the bottom surface of the coring sample holder 1069 (or some other known object or surface not the coring sample), if a coring sample is not present.

Based upon the measured distance between the first position (retracted position) and the second position (extended position) of the handling piston 1081, the presence of a coring sample within the coring sample holder 1069 may be determined. If the presence of a coring sample is determined to be present within the coring sample holder 1069, the length of the coring sample may be determined based upon the measured distance between the first position and the second position of the handling piston 1081. Otherwise, if a coring sample is determined to not be present within the coring sample holder 1069, the coring tool 1021 may be used to attempt to obtain another coring sample from the formation before the coring sample holder 1069 is stored within the storage area 1061.

For example, with reference to FIG. 10, the coring bit of the coring tool 1021 may successfully obtain a coring sample 1093A from the wall of a borehole, thereby having the coring sample 1093A disposed within the coring sample holder 1069A, as discussed above. As such, the handling piston 1081 may be disposed at a position 1095A (retracted position), in which the handling piston 1081 may move and extend into a position 1095B (extended position), in which the handling piston 1081 may engage the top surface of the coring sample 1093A. However, if the coring sample 1093A is not present within the coring sample holder 1069A, rather than stopping at the position 1095B, the handling piston 1081 may instead be able to move and extend into a position 1095C (also an extended position).

In such embodiments, the distance between the movement of the handling piston 1081 between a first position, such as the position 1095A, and a second position, such as the position 1095B and/or 1095C, may be measured. This measured distance may then be compared with a predetermined distance, such as a predetermined distance defined by the distance from the position 1095A, when the handling piston 1081 may be within a retracted position, and the position 1095C, when the handling piston 1081 may be within an extended position such that the handling piston 1081 engages the bottom of the coring sample holder 1069A. Based upon the comparison of the measured distance with the predetermined distance, the presence of a coring sample 1095A and/or the length of the coring sample 1095A may be determined.

As such, in accordance with one or more embodiments disclosed herein, the measured distance and the predetermined distance may be compared against each other by subtracting one of the distances from the other. For example, a measured distance D_(M), such as the distance of the movement of the handling piston 1081 from a first position to a second position, may be subtracted from a predetermined distance D_(P), such as the distance of the movement for the handling piston 1081 to extend from the position 1095A to the position 1095C, thereby resulting in a differential distance D_(D), as shown below:

D _(D) =D _(P) −D _(M)  Equation (1)

If the measured distance D_(M) and the predetermined distance D_(P) are substantially equal to each other, such that the measured distance D_(M) of the handling piston 1081 may be able to move from the position 1095A to the position 1095C in one embodiment, the differential distance D_(D) may be substantially equal to zero, or may be a minimal amount. In such a scenario, with the differential distance D_(D) being substantially zero or a minimal amount, one may determine a coring sample is not present within the coring sample holder 1069A of the coring tool 1021, as the handling piston 1081 was able to move from the position 1095A to the position 1095C without being impeded by the presence of a coring sample within the coring sample holder 1069A.

However, if the measured distance D_(M) and the predetermined distance D_(P) are not substantially equal to each other, such that the measured distance D_(M) of the handling piston 1081 may be able to move from the position 1095A to the position 1095B in one embodiment, the differential distance D_(D) may be substantially more than a minimal amount. In such a scenario, with the differential distance D_(D) being substantially more than a minimal amount, one may determine a coring sample is present within the coring sample holder 1069A of the coring tool 1021, as the handling piston 1081 was impeded from moving from the position 1095A and past the position 1095B, in which the top surface of the coring sample 1093A may be disposed at the position 1095B. Further, in such a scenario, as the differential distance D_(D) may be substantially more than a minimal amount, the differential distance D_(D) may be substantially equal to the length L_(C) of the sampling core 1093A. For example, with reference to FIG. 10, the length L_(C) of the sampling core 1093A, which corresponds to the differential distance D_(D) from Equation (1), may be substantially equal to the measured distance D_(M), the distance measured between the position 1095A and the position 1095B, subtracted from the predetermined distance D_(P), the distance known between the position 1095A and the position 1095C.

As such, in accordance with one or more embodiments, a threshold value may be selected for the differential distance D_(D) such that if the differential distance D_(D) is greater than the threshold value, one may determine that a coring sample is present within a coring sample holder, and if the differential distance D_(D) is no greater than the threshold value, one may determine that a coring sample is present within a coring sample holder. For example, in one embodiment, a threshold valve of about 0.25 inches (0.64 centimeters) may be selected such for the differential distance D_(D) such that if the differential distance D_(D) is greater than about 0.25 inches (0.64 centimeters), one may determine that a coring sample is present within a coring sample holder, and if the differential distance D_(D) is no greater than about 0.25 inches (0.64 centimeters), one may determine that a coring sample is not present within a coring sample holder. In such embodiments, the measured length L_(C) of the sampling core may need to exceed the threshold valve, such as of about 0.25 inches (0.64 centimeters), to determine that a sampling core is present within the coring sample holder. Further, though a threshold value may be selected and used within one or more embodiments disclosed herein, such as a threshold value of about 0.25 inches (0.64 centimeters), those having ordinary skill in the art will appreciate the present disclosure contemplates other embodiments, such as by using threshold values of different amounts, or by also by excluding the use of a threshold amount.

Those having ordinary skill in the art will appreciate that, though the present disclosure discusses one or more methods, the present disclosure is not so limited to only the embodiments disclosed, as other embodiments are contemplated for the present disclosure. For example, as shown within FIG. 10, one or more other positions may be used in addition or in alternative to the positions 1095A-1095C discussed above. As such, in one embodiment, rather than using the position 1095C, another position may be used, such as a position 1095D may be used, in which the handling piston 1081 may engage a surface or component within the coring sample holder 1069A (such as a retaining device within the coring sample holder 1069A). In such an embodiment, rather than using the position 1095C within the predetermined distance, for example, the position 1095D may instead be used. Thus, one or more positions may be used in addition or in alternative to the positions shown in FIG. 10.

Further, one or more other methods may be used in addition or in alternative to the methods discussed above when comparing the predetermined distance with the measured distance to determine the presence of a coring sample within a coring tool. For example, rather than subtracting the measured distance from the predetermined distance, as discussed above and shown with respect to Equation (1), the measured distance may instead be divided by the predetermined distance. Such a comparison of the measured distance with the predetermined distance may enable a fraction and/or a percentage to be determined, in which the fraction and/or percentage may enable one to determine the presence of a coring sample within the coring tool. As such, though the present disclosure is discussed and described with respect to a limited number of embodiments disclosed herein, those having ordinary skill in the art will appreciate that the present disclosure contemplates one or more other methods and embodiments.

As such, in accordance with one or more embodiments, after the presence of a coring sample within the coring tool has been determined, the coring tool may either be used to re-drill for a coring sample and/or may be used to dispose the coring sample within the storage area of the coring tool. For example, in an embodiment in which a coring sample is determined as present within a coring sample holder of the coring tool, the coring sample holder may be disposed within the storage area of the coring tool. As such, another coring sample may then be attempted to be retrieved with the coring tool. Further, in an embodiment in which a coring sample is determined as not present within a coring sample holder of the coring tool, the coring bit may be used to attempt obtaining a coring sample again for the coring sample holder. As such, this may prevent a coring sample holder that is substantially empty from being disposed within the storage area of the coring tool.

Referring now to FIGS. 11 and 12, multiple views of flow charts of methods 1100 and 1200 to drill with a coring tool in accordance with one or more embodiments of the present disclosure are shown. Particularly, FIG. 11 shows a flow chart of a method 1100 to drill with a coring tool if a coring sample is determined as present within the coring tool. Further, FIG. 12 shows a flow chart of a method 1200 to drill with a coring tool if a coring sample is determined as not present within the coring tool.

Referring specifically to FIG. 11, the method 1100 may include drilling into a wall of a borehole 1110, in which a coring bit of a coring tool may be used to drill into the wall of the wellbore. As such, when drilling into the borehole, the coring bit may attempt to retrieve a coring sample from a formation that the borehole is formed within.

Further, the method 1100 may include moving the coring bit from a first position to a second position 1120 and moving a handling piston from a first position to a second position 1130. For example, the coring bit may move from a first position, such as a coring position, to a second position, such as an ejection position. Further, the handling piston may then move from a first position, such as a retracted position, to a second position, such as an extended position. With such movement, the handling piston may be able to move through the coring bit, such that a coring sample, if present within the coring tool, and the coring sample holder may be urged out from the coring bit and into a defined position, such as by having the coring sample holder positioned within a transfer tube and/or a shifter. Further, in one or more embodiments, the coring sample holder may not be retained within the coring bit, such as during drilling with the coring bit. In such embodiments, the coring sample may be urged out of the coring bit and into the coring sample holder. Furthermore, with such movement, the handling piston may then stop at a second position, such as at the top surface of a coring sample disposed within the coring sample holder.

The method 1100 may then continue on to measure the handling piston movement from the first position to the second position 1140 and determine the coring sample presence within the coring tool 1150. For example, the distance of the movement of the handling piston between the first position, such as the retracted position, and the second position, such as the extended position, in which the handling piston engaged with the top surface of the coring sample, may be measured. This measured distance may be provided, for example, with one or more sensors or devices disposed within the coring tool and operably coupled to the handling piston. For example, the handling piston may be connected to an electrical motor, such as through a lead screw. The distance may then be measured by a rotational position sensor, such as a resolver, coupled with the electrical motor. Further, based upon the measured distance, the presence of a coring sample may be determined, such as by comparing the measured distance with a predetermined distance, as discussed above.

Referring still to FIG. 11, because a coring sample may be determined as present within the coring tool in the method 1100, the method 1100 may further include determining the length of a coring sample within the coring tool 1160 and disposing the coring sample within a storage area 1170. For example, as a measured distance of the handling piston was determined, a length of the coring sample may be determined, such as by comparing the measured distance with the predetermined distance, as discussed above. Further, because a coring sample is determined as present within the coring tool in method 1100, the coring sample and the coring sample holder may be disposed within the storage area of the coring tool. As such, in one or more embodiments, another coring sample holder may then be made available in the transfer tube and/or the coring bit of the coring tool, in which the other coring sample holder may be used to retrieve yet another coring sample with the coring tool.

Referring now specifically to FIG. 12, the method 1200 may be used to drill into the wall of a wellbore, in which a coring sample may not be retrieved, at least upon the first attempt. As such, the method 1200 may include one or more steps similar to that of the method 1100 shown in FIG. 11. For example, as shown, the method 1200 may include steps 1210-1250 that may be substantially similar to that of steps 1110-1150 of the method 1100. However, in method 1200, when the handling piston moves from a first position, such as a retracted position, to a second position, such as an extended position, the handling piston may not engage with the upper surface of the coring sample. Rather, because a coring sample may not have substantially been received within the coring sample holder, the handling piston may engage the bottom surface of the coring sample holder, or another known surface within the coring sample holder (such as a retaining mechanism), in which the handling piston may then stop as this second position. As such, a coring sample may be determined as not present within the coring tool and the coring sample holder, such as by comparing the measured distance of the movement of the handling piston between the first position and the second position, as discussed above.

Thus, because a coring sample may be determined as not present within the coring tool in the method 1200, the method 1200 may further include moving the handling piston from the second position back to the first position 1260, and then moving the coring bit from the second position back to the first position 1265. For example, the handling piston may be moved from the second position, such as the extended position, back to the first position, such as the retracted position. In one or more embodiments in which the coring sample holder is configured to fit and/or be received within the coring bit of the coring tool, the coring sample holder may be brought back into the coring bit. Otherwise, in other embodiments, the coring sample holder may remain in a position in the transfer tube of the coring tool. Further, as the handling piston is no longer disposed within the coring bit, as the handling piston may be disposed within the retracted piston, the coring bit may be rotated from the second position, such as the ejection position, back to the first position, such as the coring position.

Further, the method 1200 may include re-drilling into the wall of the wellbore 1270, in which a coring bit of a coring tool may be used to re-drill into the wall of the wellbore. As such, when re-drilling into the borehole, the coring bit may again attempt to retrieve a coring sample from a formation that the borehole is formed within.

Furthermore, the method 1200 may include moving the coring bit from the first position to the second position 1275 and moving a handling piston from the first position to a third position 1280. For example, the coring bit may move from the first position, such as the coring position, to the second position, such as the ejection position. The handling piston may then move from the first position, such as the retracted position, to a third position, such as another an extended position. With such movement, the handling piston may be able to move through the coring bit again, such that a coring sample, if present within the coring tool, and/or the coring sample holder may be urged out from the coring bit and into a defined position, such as by having the coring sample holder positioned within a transfer tube and/or a shifter. Additionally, with such movement, the handling piston may then stop at a third position, in which the third position may, for example, be at the top surface of a coring sample disposed within the coring sample holder or, alternatively, be at the bottom surface of the coring sample holder.

The method 1200 may then continue on to measure the handling piston movement from the first position to the third position 1285 and determine the coring sample presence within the coring tool 1290. For example, the distance of the movement of the handling piston between the first position, such as the retracted position, and the third position, such as another extended position, may be measured. As such, based upon the measured distance, the presence of a coring sample may be determined, such as by comparing the measured distance with a predetermined distance, as discussed above. Accordingly, if a coring sample is determined as present within the coring tool in step 1290, the method 1200 may then follow the steps 1160 and 1170 of the method 1100 shown in FIG. 11, or if a coring sample is determined as not present within the coring tool in step 1290, the method 1200 may then repeat one or more of the steps 1260-1290 to re-drill and attempt to receive a coring sample within the coring tool again.

In accordance with one or more embodiments disclosed herein, the handling piston may be able to move at a duty cycle less than 100 percent. For example, in one embodiment, the handling piston may be able to move at a duty cycle of about 20 percent. In such an embodiment, this may enable the handling piston to move with a slower and more desired speed and/or a smaller and more desired force. As such, a smaller duty cycle for the handling piston may enable the piston to be more sensitive to the presence of a coring sample, in which the handling piston may be able to more accurately stop at a second position within a coring tool. Accordingly, the handling piston may move at various duty cycles within the coring bit to perform various tasks. For example, the handling piston may move at a higher duty cycle when attempting to urge a coring sample out from a coring bit, and may move at a lower duty cycle when moving to stop at the second position to detect the presence of the coring sample. When moving at a duty cycle in accordance with one or more embodiments disclosed herein, the handling piston may then stop in movement, such as by a stalling of the motor driving the handling piston. As such, in one embodiment, the stopping in movement of the handling piston may then be detected when the measured position of the handling piston remains constant with time, a position that may be calculated from a resolver signal, while the motor driving coupled to the handling piston has power applied thereto (e.g., an electrical current) to drive the handling piston.

Further, in accordance with one or more embodiments of the present disclosure, a coring tool of the present disclosure may include one or more sensors included therein and/or operably coupled thereto. As such, in one embodiment, a coring tool may include a pressure sensor operably coupled to the handling piston, in which the pressure sensor may be able to measure pressure received upon the handling piston. In such an embodiment, the handling piston may stop in movement, such as stop at the second position in movement, when the pressure measured by the pressure sensor reaches or exceeds a predetermined pressure. For example, a predetermined pressure may be selected, such as a threshold pressure, in which once the measured pressure exceeds the predetermined pressure, the handling piston may stop in movement. As such, this may enable the handling piston to stop at the second position, such as when the handling piston engages the top surface of a coring sample or engages the bottom surface of a coring sample holder. Those having ordinary skill in the art will appreciate that in addition or in alternative to a pressure sensor, or any other type of sensor, other devices may be used to stop the handling piston at a desired second position in accordance with one or more embodiments disclosed herein.

Further, aspects of embodiments disclosed herein, such as detecting a coring sample presence and measuring the length of a coring sample, may be implemented on any type of computer regardless of the platform being used. For example, as shown in FIG. 13, a networked computer system 1310 that may be used in accordance with an embodiment disclosed herein includes a processor 1320, associated memory 1330, a storage device 1340, and numerous other elements and functionalities typical of today's computers (not shown). The networked computer system 1310 may also include input means, such as a keyboard 1350 and a mouse 1360, and output means, such as a monitor 1370. The networked computer system 1310 is connected to a local area network (LAN) or a wide area network (e.g., the Internet) (not shown) via a network interface connection (not shown). Those skilled in the art will appreciate that these input and output means may take many other forms. Additionally, the computer system may not be connected to a network. Further, those skilled in the art will appreciate that one or more elements of aforementioned computer 1310 may be located at a remote location and connected to the other elements over a network. As such, a computer system, such as the networked computer system 1310, and/or any other computer system known in the art may be used in accordance with embodiments disclosed herein, such as by having a computer system coupled to and/or included within a coring tool of the present disclosure.

Embodiments disclosed herein may provide for one or more of the following advantages. A tool and method in accordance with the present disclosure may be included within one or more of the embodiments shown in FIGS. 1-6, in addition to being included within other tools and/or devices that may be disposed downhole within a formation. Further, a tool and a method in accordance with one or more embodiments of the present disclosure may be able to detect the presence of a coring sample within a coring sample holder before the coring sample holder is disposed within the storage area of the coring tool. This may enable the coring tool to re-drill to attempt to retrieve a coring sample for the coring sample holder, thereby preventing an empty coring sample holder from being disposed within the storage area of the coring tool. Furthermore, a tool and a method in accordance with one or more embodiments of the present disclosure may be able to determine the length of a coring sample within a coring tool.

In accordance with one or more aspects of the present disclosure, one or more embodiments disclosed herein relate to a method to detect the presence of a coring sample within a coring tool. The method includes moving a handling piston of the coring tool from a first position to a second position with respect to the coring tool, the handling piston moving through a coring bit to the second position, measuring a distance of the movement of the handling piston between the first position and the second position, comparing the measured distance with a predetermined distance, and determining if the coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.

In accordance with one or more aspects of the present disclosure, one or more embodiments disclosed herein relate to a method to drill within a borehole with a coring tool, the method includes drilling into a wall of the borehole with a coring bit of the coring tool, the coring bit disposed in a coring position with respect to the coring tool and the coring tool having an axis extending therethrough, rotating the coring bit from the coring position to an ejection position with respect to the coring tool, extending a handling piston of the coring tool from a retracted position to an extended position with respect to the coring tool, measuring a distance of the movement of the handling piston between the retracted position and the extended position, comparing the measured distance with a predetermined distance, and determining if a coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.

In accordance with one or more aspects of the present disclosure, one or more embodiments disclosed herein relate to a method to detect the presence of a coring sample within a coring tool. The method includes moving a transporter of the coring sample from a first position to a second position with respect to the coring tool, measuring the distance of the movement of the transporter between the first position and the second position, comparing the measured distance with a predetermined distance, and determining if the coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.

The foregoing outlines feature several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.

The Abstract at the end of this disclosure is provided to comply with 37 C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 

1. A method to detect the presence of a coring sample within a coring tool, the method comprising: moving a handling piston of the coring tool from a first position to a second position with respect to the coring tool, the handling piston moving through a coring bit to the second position; measuring the distance of the movement of the handling piston between the first position and the second position; comparing the measured distance with a predetermined distance; and determining if the coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.
 2. The method of claim 1, wherein, if determined the coring sample is present within the coring tool, the method further comprises: determining a length of the coring sample based upon the measured distance of the movement of the handling piston.
 3. The method of claim 1, wherein, if determined the coring sample is present within the coring tool, the method further comprises: disposing the coring sample within a storage area of the coring tool.
 4. The method of claim 1, wherein, if determined the coring sample is not present within the coring tool, the method further comprises: moving the handling piston from the second position to the first position with respect to the coring tool; moving the coring bit from a second position to a first position with respect to the coring tool; and re-drilling into a wall of the borehole with the coring bit of the coring tool.
 5. The method of claim 4, further comprising: moving the coring bit from the first position to the second position with respect to the coring tool; moving the handling piston of the coring tool from the first position to a third position with respect to the coring tool, the handling piston being at least partially disposed within the coring bit in the third position; measuring a second distance of the movement of the handling piston between the first position and the third position; and determining if a coring sample is present within the coring tool based upon the comparison of the second measured distance with the predetermined distance
 6. The method of claim 1, wherein the comparing the measured distance with the predetermined distance comprises: subtracting the measured distance from the predetermined distance, thereby resulting in a differential distance between the measured distance and the predetermined distance; and comparing the differential distance with a threshold value.
 7. The method of claim 1, wherein the moving the handling piston of the coring tool from the first position to the second position with respect to the coring tool comprises: moving the handling piston from the first position with respect to the coring tool; measuring pressure upon the handling piston with a pressure sensor; and stopping movement of the handling piston when the measured pressure upon the handling piston is more than a predetermined pressure; wherein the handling piston stops in movement at the second position with respect to the coring tool.
 8. The method of claim 1, wherein, when the handling piston moves from the first position to the second position with respect to the coring tool, the handling piston moves, at least partially, at a duty cycle less than about 100 percent.
 9. The method of claim 1, wherein the moving a coring bit from a first position to a second position with respect to the coring tool comprises rotating the coring bit from a coring position to an ejection position with respect to the coring tool.
 10. The method of claim 1, wherein the moving the handling piston of the coring tool from the first position to the second position with respect to the coring tool comprises extending the handling piston of the coring tool from a retracted position to an extended position with respect to the coring tool.
 11. A method to drill within a borehole with a coring tool, the method comprising: drilling into a wall of the borehole with a coring bit of the coring tool, the coring bit disposed in a coring position with respect to the coring tool and the coring tool having an axis extending therethrough; rotating the coring bit from the coring position to an ejection position with respect to the coring tool; extending a handling piston of the coring tool from a retracted position to an extended position with respect to the coring tool; measuring a distance of the movement of the handling piston between the retracted position and the extended position; comparing the measured distance with a predetermined distance; and determining if a coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.
 12. The method of claim 11, wherein, if determined the coring sample is present within the coring tool, the method further comprises: determining a length of the coring sample if determined the coring sample is present within the coring tool; and storing the coring sample within a storage area of the coring tool if determined the coring sample is present within the coring tool.
 13. The method of claim 12, wherein the coring sample is disposed within a coring sample holder before disposing the coring sample within the storage area of the coring tool.
 14. The method of claim 12, further comprising: retracting the handling piston from the extended position to the retracted position with respect to the coring tool; rotating the coring bit from the ejection position to the coring position with respect to the coring tool; and re-drilling into the wall of the borehole with the coring bit of the coring tool. rotating the coring bit from the coring position to the ejection position with respect to the coring tool; extending the handling piston of the coring tool from the retracted position to a second extended position with respect to the coring tool, the handling piston being at least partially disposed within the coring bit in the second extended position; measuring a second distance of the movement of the handling piston between the retracted position and the second extended position; comparing the second measured distance with the predetermined distance; and determining if a second coring sample is present within the coring tool based upon the second comparison of the measured distance with the predetermined distance.
 15. The method of claim 11, wherein, if determined the coring sample is not present within the coring tool, the method further comprises: re-drilling into the wall of the borehole with the coring bit of the coring tool if determined the coring sample is not present within the coring tool.
 16. The method of claim 11, wherein the handling piston stops in movement at the extended position when the pressure upon the handling piston is more than a predetermined pressure.
 17. The method of claim 11, wherein, when the handling piston extends from the first position to the second position with respect to the coring tool, the handling piston extends, at least partially, at a duty cycle less than about 100 percent.
 18. The method of claim 11, wherein the comparing the measured distance with the predetermined distance comprises: subtracting the measured distance from the predetermined distance, thereby resulting in a differential distance between the measured distance and the predetermined distance; and comparing the differential distance with a threshold value.
 19. A method to detect the presence of a coring sample within a coring tool, the method comprising: moving a transporter of the coring tool from a first position to a second position with respect to a borehole; measuring a distance of the movement of the transporter between the first position and the second position; comparing the measured distance with a predetermined distance; and determining if the coring sample is present within the coring tool based upon the comparison of the measured distance with the predetermined distance.
 20. The method of claim 19, wherein the transporter comprises a handling piston.
 21. The method of claim 20, further comprising: drilling into a wall of the borehole with a coring bit of the coring tool, the coring bit disposed in a first position with respect to the coring tool and the coring tool having an axis extending therethrough; and moving the coring bit from the first position to a second position with respect to the coring tool. 